All-Dielectric Transparent Metamaterial Absorber With Encapsulated Water

An all-dielectric transparent metamaterial absorber with encapsulated water is demonstrated in this paper. Because the proposed absorber is realized using only water and polydimethylsiloxane (PDMS) without any conductive patterns, optical transparency is achieved. In addition, the high dielectric loss of water renders it a good candidate for an electromagnetic absorber. The absorptivity is increased by encapsulating the water within the PDMS, and the absorptivity of the proposed absorber is numerically compared with that of the PDMS and water with the same size. When the proposed absorber is realized using two layers, 92.5% absorptivity is achieved at 10.8 GHz, and the absorptivity exceeds 90% in the range of 10.45 to 11.20 GHz, which corresponds to 6.9% bandwidth. Therefore, the proposed absorber has advantages of high transparency, low cost, wide absorption bandwidth, and eco-friendly fabrication.